But "nothing extraordinary" happened between Corey Brown and his parents before he left home late Tuesday evening as a snowstorm descended on the central Iowa city of 27,000, Marshalltown police chief Michael Tupper said in an interview Monday.

Brown was last seen Tuesday night, when he left his parents’ home on Marshalltown's south side after having a "disciplinary discussion" in which his phone was taken away, Tupper said at a news conference Thursday.

Since then, Tupper said he's heard a lot of "unfair" assumptions that some sort of big fight occurred between Brown and his parents. But, he said, there's no proof of an argument or anger between the young teen and his parents the night he left.

"I can't emphasize enough that this speculation about why he left ... it's not a fair depiction," the chief said Monday. "Nothing extraordinary happened at home that caused this to occur."

Tupper estimated his department handles one missing person case a week, on average, adding that, in most instances, it involves a minor, and the cases are resolved quickly.

During the high-profile search for Brooklyn native Mollie Tibbetts, the Iowa Division of Criminal Investigation said that more than 4,300 juveniles were reported missing in the 2017 fiscal year, an average of about 12 per day.

Typically, the lost children are runaways, a vast majority of whom were found or returned home within 24 hours, the agency said.

"The [Brown] family has already been traumatized enough," Tupper said. "They don't need to be re-victimized. They need all the support they can get right now."

The Marshalltown Police Department is still totaling the resources used in the search, but Tupper estimated between 50 and 80 trained professionals were out searching each of the five days. Though they utilized search dogs and attempted to use a drone when weather conditions allowed, most of the search work was done by ground teams.

Anyone with information about Brown's death is encouraged to call the Marshalltown Police Department at 641-754-5725 or Crime Stoppers at 641-753-1234. Information can also be sent by texting the word "marshall" with any information to 274637 or online at MarshallCountyCS.com.